> For the complete documentation index, see [llms.txt](https://telephony.shounakmulay.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://telephony.shounakmulay.dev/listen-incoming-sms.md).

# Listen Incoming SMS

## Setup

{% hint style="danger" %}
**Requires *****`RECEIVE_SMS`***** permission.**
{% endhint %}

To listen to incoming SMS add the `RECEIVE_SMS` permission to your `AndroidManifest.xml` file and register the `BroadcastReceiver`.

{% code title="AndroidManifest.xml" %}

```markup
<manifest>
    <uses-permission android:name="android.permission.RECEIVE_SMS"/>

    <application>
        ...
        ...

        <receiver android:name="com.shounakmulay.telephony.sms.IncomingSmsReceiver"
            android:permission="android.permission.BROADCAST_SMS" android:exported="true">
            <intent-filter>
            <action android:name="android.provider.Telephony.SMS_RECEIVED"/>
            </intent-filter>
        </receiver>

    </application>
</manifest>
```

{% endcode %}

## Usage

&#x20;**1.** Create a **top-level static function** to handle incoming messages when app is not is foreground.

{% hint style="warning" %}
**Avoid heavy computations in the background handler as Android system may kill long running operations in the background.**
{% endhint %}

```dart
backgrounMessageHandler(SmsMessage message) async {
    //Handle background message    
}

void main() {
  runApp(MyApp());
}
```

**2.** Call `listenIncomingSms` with a foreground `MessageHandler` and pass in the static `backgrounMessageHandler`.

{% hint style="info" %}
**Multipart message will be grouped together and delivered as a single SMS to the listenIncomingSms() function.**
{% endhint %}

```dart
telephony.listenIncomingSms(
     onNewMessage: (SmsMessage message) {
         // Handle message
     },
     onBackgroundMessage: backgroundMessageHandler
 );
```

#### Preferably should be called early in app lifecycle.

**3.** As of the `1.12` release of Flutter, plugins are automatically registered. This will allow you to use plugins as you normally do even in the background execution context.

```dart
backgrounMessageHandler(SmsMessage message) async {
     // Handle background message

     // Use plugins
     Vibration.vibrate(duration: 500);
 }
```

**4.** If you do not wish to receive incoming SMS when the app is in background, just do not pass the `onBackgroundMessage` parameter.

Alternatively if you prefer to expecility disable background execution, set the `listenInBackground` flag to `false`.

```dart
telephony.listenIncomingSms(
     onNewMessage: (SmsMessage message) {
         // Handle message
     },
     listenInBackground: false
 );
```


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://telephony.shounakmulay.dev/listen-incoming-sms.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.